[NH:1]1[CH:5]=[CH:4][CH:3]=[N:2]1.[H-].[Na+].Br[CH2:9][C:10]1[CH:19]=[CH:18][C:13]([C:14]([O:16][CH3:17])=[O:15])=[CH:12][CH:11]=1>CN(C=O)C>[N:1]1([CH2:9][C:10]2[CH:19]=[CH:18][C:13]([C:14]([O:16][CH3:17])=[O:15])=[CH:12][CH:11]=2)[CH:5]=[CH:4][CH:3]=[N:2]1Under nitrogen atmosphere, a solution of pyrazole (743 mg) in DMF (10 mL) was cooled to 0° C., and thereto was added NaH (480 mg, 60%). The mixture was stirred at 0° C. for 10 minutes, and stirred at room temperature for one hour. Methyl 4-(bromomethyl)benzoate (2.50 g) was added to the mixture, and the mixture was stirred at room temperature for 2 hours. To the mixture was added ice water (50 mL), and extracted three times with ethyl acetate-toluene, and dried over MgSO4. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel column (hexane/ethyl acetate=10/1→3/1) to give methyl 4-(1H-pyrazol-1-ylmethyl)benzoate (2.17 g, 92%).
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